1. Field of the Invention
The present invention relates to arc discharge lamps, and more particularly, to ultra-compact arc discharge lamps for portable applications.
2. Background Art
Arc discharge lamps have been widely used in fixed and portable projectors because of the ability of arc discharge lamps to produce high intensity light. In a conventional arc discharge lamp, high intensity light is produced by arc discharge in an ionized gas. Conventional arc discharge lamps typically require a high initial starting voltage which ionizes or breaks down the gas inside a hermetically sealed lamp envelope.
A conventional arc discharge lamp typically has two conducting electrodes which are positioned close to each other inside the lamp envelope. The gas inside the lamp envelope is initially ionized by applying a high voltage on one or both of the electrodes. In a typical igniter circuit for a conventional two-electrode arc discharge lamp, a large and heavy igniter transformer is usually required to provide a high voltage for ionizing the gas inside the lamp envelope and to support a large current through the two electrodes in the arc discharge lamp to sustain illumination once the arc discharge begins.
In a conventional two-electrode arc discharge lamp system, an igniter transformer is required not only to produce a high voltage for igniting the arc discharge lamp by ionizing the gas inside the lamp envelope, but also to pass a large current through the two electrodes to maintain arc discharge after the gas inside the lamp envelope is ionized. The igniter transformer is typically a large and heavy magnetic component in a conventional two-electrode arc discharge lamp system. An increase in the power of the arc discharge lamp usually necessitates an increase in the size and weight of the igniter transformer. The size and weight of the igniter transformer in a conventional two-electrode arc discharge lamp system makes it unattractive for use in lightweight portable projectors that produce high-intensity illumination.
Therefore, there is a need for a compact and lightweight arc discharge lamp system that is suitable for use in a lightweight high-power portable projector. Furthermore, there is a need for an arc discharge lamp system for a lightweight portable projector that uses a low-voltage DC power source.